The general object of our biomedical image processing program is to apply modern techniques for automatic image processing to the performance of appropriate and necessary biomedical observations. The goal of the research project proposed herein is to develop an automatic cytogenetic analysis system for radiation health monitoring purposes in order to make feasible the use of readily generated quantitative information concerning chromosome aberrations in populations potentially or actually exposed to ionizing radiation. Such populations include workers in the nuclear industry, members of the public inadvertently exposed to accidentally released radioactivity, people whose living environment is demonstrated to contain a higher level of natural or man-made radioactivity than the usual and individuals undergoing diagnostic or therapeutic X-ray or radioisotope exposure for medical reasons. The project involves the use and ongoing development of an automated microscope to scan cytogenetic slide preparations, locate the usable dividing cells, focus and then digitize these cells; systems engineering for control of the microscope, and transfer and storage of the large quantity of data generated; and software development for analysis of cytogenetic data and its correlation with exposure data. Our specific aim is to combine and modify the abnormal recognition software and the automated microscope to produce an efficient automatic cytogenetic analysis system. The system will process irradiated blood cells and provide data for improvements in the operating efficiency of hardware and recognition software subsystems. The data developed will also provide information concerning the sensitivity of cytogenetic monitoring for the effects of low radiation exposure levels.